[Significance of hepatitis B core antibody as the only marker of hepatitis B infection]. / Significado de la reactividad aislada anti-HBc como único marcador de infección de la hepatitis B.

INTRODUCTION: Little is known about the clinical significance of the "anti-HBc alone" serological profile (absence of HBsAg and anti-HBs) in HBV infections. The objective of the present study was to estimate the prevalence of the anti-HBc alone immunological profile and the clinical-epidemiological characteristics of patients with this profile. METHODS: Prospective, cross-sectional, descriptive study performed in 2002 and including patients with anti-HBc alone (HBsAg-negative, anti-HBs-negative and anti-HBc-positive). All the cases identified underwent the following microbiological tests: IgM anti-HBc, HBeAg, anti-HBe, anti-HDV, anti-HCV, anti-HIV, as well as HBV-DNA testing by qualitative nested-PCR. Furthermore, studies of serum biochemical parameters, blood counts and coagulation, as well as a clinical-epidemiological interview were performed in all patients. RESULTS: Among 3900 patients studied, 195 (5%) presented the anti-HBc alone profile (48% were > 65 years old). Residual anti-HBs (< 10 mUI/mL) was found in 44% of cases and 33% were anti-HBe positive. HCV or HIV coinfection were seen in 38% and 8%, respectively. HBV-DNA was detected in 4.2% (5/120) of cases. Epidemiologically, detection of anti-HBc alone was casual in 60% of patients, whereas the remaining cases had a history of chronic liver disease (82% of these were anti-HCV positive). In a high percentage (63%) the transmission mechanism of HBV infection was unknown (11% intravenous drug abuser, 10% surgery, 6% transfusions). CONCLUSION: The anti-HBc alone pattern is a frequent finding, particularly in patients > 65 years old and in HCV or HIV coinfected patients. Although HBV-DNA was detected in a small percentage of cases, this test could be indicated in certain clinical situations (liver disease, coinfection, donors). Furthermore, this profile seems to be related with HCV infection; hence, we consider anti-HCV detection necessary in all patients with anti-HBc alone.

Significado de la reactividad aislada anti-HBc como único marcador de infección de la hepatitis B / Significance of hepatitis B core antibody as the only marker of hepatitis B infection

INTRODUCCIÓN. El significado de la presencia aislada de anticuerpos anti-HBc frente al virus de la hepatitis B (VHB),en ausencia de HBsAg y de anti-HBs, es escasamente conocido. El objetivo del presente estudio ha sido estimar la prevalencia, así como las características clínico-epidemiológicas de los pacientes con perfil inmunológico anti-HBc aislado. MÉTODOS. Estudio prospectivo, transversal y descriptivo realizado durante el año 2002 en pacientes con anti-HBcaislado (AgHBs negativo, anti-HBs 65 años). El 44% presentaban anti-HBs residuales o de bajo nivel (< 10 mU/ml) y un 33% eran anti-HBepositivos. En el 38% y en el 8% de los casos existía coinfección por el VHC y el VIH, respectivamente. Se detectó ADN-VHB en el 4,2% (5/120) de los casos. Epidemiológicamente, en el 60% de los pacientes la detección anti-HBc aislado fue casual, mientras que en el resto existían antecedentes de hepatopatía crónica(el 82% eran anti-VHC positivos). En un elevado porcentaje(63%) el mecanismo de transmisión de la infección por VHB era desconocido (11% ADVP; 10%, cirugía; 6%, transfusiones). CONCLUSIÓN. El patrón anti-HBc aislado es un hallazgo frecuente en nuestro medio, especialmente en pacientes mayores de 65 años y en coinfectados por el VHC o el VIH. Aunque en una baja proporción de pacientes se detecta ADN-VHB, esta prueba podría estar indicada bajo determinadas situaciones clínicas (hepatopatía,coinfecciones, donantes). Además, este patrón parece relacionado con la infección por el VHC, por lo se hace necesaria la detección de anti-VHC en todos los pacientescon anti-HBc aislado (AU)

INTRODUCTION. Little is known about the clinical significance of the “anti-HBc alone” serological profile (absence of HBsAg and anti-HBs) in HBV infections. The objective of the present study was to estimate the prevalence of the anti-HBc alone immunological profile and the clinical-epidemiological characteristics of patients with this profile METHODS. Prospective, cross-sectional, descriptive study performed in 2002 and including patients with anti-HBc alone (HBsAg-negative, anti-HBs-negative andanti-HBc-positive). All the cases identified underwent the following microbiological tests: IgM anti-HBc, HBeAg, anti-HBe, anti-HDV, anti-HCV, anti-HIV, as well asHBV-DNA testing by qualitative nested-PCR. Furthermore, studies of serum biochemical parameters, blood counts and coagulation, as well as a clinical-epidemiological interview were performed in all patients. RESULTS. Among 3900 patients studied, 195 (5%) presented the anti-HBc alone profile (48% were > 65 years old).Residual anti-HBs ( 65 years old and in HCVor HIV coinfected patients. Although HBV-DNA was detected in a small percentage of cases, this test could be indicated in certain clinical situations (liver disease, coinfection, donors). Furthermore, this profile seems to be related with HCV infection; hence, we consider anti-HCV detection necessary in all patients with anti-HBc alone (AU)